Ignition devices



June 17, 1958 w. M. KOHRING 2,839,592

IGNITION DEVICES Filed July 1, 1953 INVENTOR.

A TTOENEYS.

United States Patent Ofiice 2,839,592 Patented June 17, 1958 IGNITION DEVICES Wilbur M. Kohring, Cleveland, Ohio Application July 1, 1953, Serial No. 365,395

4 Claims. (Cl. 123-148) This invention relates to ignition coils for internal combustion engine equipment, and more particularly hermetically sealed units, and in one preferred form involves sealed units of coil and distributor elements in a compact and protected form. Other objects and advantages of the invention will appear from the following description.

To the accomplishment of the foregoing and related ends, said invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawing:

Fig. l is a side elevational view, partly in section, showing a coil in accordance with the invention;

Fig. 1a is an elevational view on reduced scale of a half mold with a coil in it in process of manufacture;

Fig. 2 is a side elevational view, with the upper is.)

portion in section, showing a unit including coil and distributor elements; and

Fig. 3 is a fragmentary sectional view showing a slight modification.

Referring more particularly to the drawing, there is shown in Fig. l, a construction which is hermetically sealed, including an insulation plate 2, such as of phenolaldehyde synthetic resin, silicone resin, or other similar desired material, this carrying terminals 3, such as for low tension input, and a socket 4 for another connecair-impervious envelope 7, as of polyethylene, polyvinyl,

synthetic rubber, etc., and this may be sealed as along the edges 8 to the insulation plate 2, and a vent or connection nipple may be provided through the plate to the interior to permit a connection to a source of vacuum draw-off. For the application of the encasing layer of synthetic resin insulation, the assemblage is placed in a mold having mating mold sections suitably contoured with recesses to receive the assemblage with projecting terminals, and having an inlet for supply of the insulating material in liquid form, there being left a space all around the assemblage in the mold, wherein the insulating material may be supplied as a suitably thick layer to encase the whole device. In some cases, it is preferred to perform this operation with the mold in a vacuum chamber, the liquid insulative compound being thereby de-aired, as well as the contents of the mold. This insulating material is then set or solidified, as by heating to a suitable temperature, e. g. 100-400 C., depending upon the particular material. In any case, the ignition assemblage is completely enveloped and sealed in the enveloping insulation. In special instances where desired, a metal coat m may be applied, as by electrodeposition or preferably vacuum deposition by the known technique. By providing beads or circumferential ridges 10, clamping means 6 may be applied in whatever relation is required in the mounting of the unit.

With particular advantage, the molding of the encasing insulation may be also applied to unite the elements, including the contact connections, and as shown in Fig. la the coil C is positioned in the sectional mold, of which the base portion 18 is in two mating sections, and the upper portion 19 is in two mating sections. Positioning is facilitated by pins inserted in the base portion of the mold and contacting the respective terminals. Thus, a centering pin 20 seats in a closely fitting opening in the mating base mold sections and supports the coil center, while other pins 21, 22 similarly seating in openings between the mating mold sections engage the terminals 23, 24 which are seated in appropriate recesses in the mating base mold sections, each such terminal having a lead wire 25 to the coil. The terminals 23, 24 being screw threaded, it is seen that the pins 21, 22 by having an internal threaded bore can firmly hold the terminals, and with all the supports the coil is adequately held for the subsequent operation, the upper mold sections 19 being held together by bolts through bolt holes 26. In this, the molded-on encasing insulation thus serves to unite the elements as well as encase the whole, and the end result of using a pre-forrned insulation plate as afore-provided is eliminated. Its function is here performed by the applied insulation material. As foregoing, the insulating material is supplied to the mold in liquid form through the filling opening 27, the insulating material being of synthetic resin character as previously noted. Finally by heating, the insulating material which surrounds the unit in the space left about it in the mold, is set; and the mold sections are separated from around the encased coil, and the terminal-holding pins are withdrawn, and the encased coil is removed from the mold base.

With particular advantage, a unit can include an assemblage of insulation plate 2', Fig. 2, carrying metal contacts b which are connected to metal sockets 4' to receive the plug-in cables for the respective spark plugs; and adjacent is the ignition coil C, with connections 3' laterally or 'on top as desired, for low tension input, and a high tension center contact 9 as of conventional form, carbon, graphite, or metal. This center contact is in alignment with the distributor shaft 11 which carries a rotor 12 of suitable insulation, provided with a metal spring 13 of suitable detail and form and construction to maintain contact with the center coil terminal and sweep around in succession over the annular series of contacts with connections leading to the respective spark plugs. This assemblage unit is thus seen to be of a form to seat on the support 14 of the distributor shaft 11, suitable flanging 15 making a close fit, and the unit being held to the distributor shaft support 14 suitably, as by the spring clamps which conventionally are attached to the distributor shaft support and have flanged ends which grip over shoulders on the cap unit. Here, in other words, the ignition coil assembly makes a replacement for the old style cable cap. In some instances metal shield plates S may be applied about the coil before the insulation encasement is molded on.

It will be understood that again, the assemblage of coil and insulation plate, etc., is placed in a mold and insulative synthetic resin in liquid form is supplied to provide a suitably thick layer 5 encasing the entire structure, as illustrated in Fig. '2. The sockets to receive the plug-in cables connectingto the'spa'rk plugs are directed from their positions under the ignition coil, at such angle as may be preferred in any given installation. Thus, in Fig. 2, the sockets'4" are directed at a downward inclination. This has an advantage that in event of water being splashed on the device, it will not penetrate into the sockets. Where installations require straight lateral direction for the cable-receiving sockets, these may be correspondingly positioned for the molding-on of the encasing insulation; and in some cases an upwardly-directed placement of the cable-receiving sockets 4" may be desired as shown in Fig. 3.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

I therefore particularly point out and distinctly claim as my invention:

1. As an article of manufacture, a hermetically sealed ignition device providing coil and distributor elements together, and including an insulation plate, a plurality of contacts carried in said plate, lead connections from said contacts at the other side of said plate extending laterally and downwardly inclined for the spark plug connections, a center contact in said plate for alignment with a distributor shafts rotor contactor, an ignition coil having a core and windings and a connection to said center contact, and molded-on insulation covering said coil and insulation plate and connections in a compact unit.

2. As an article of manufacture, a hermetically sealed ignition device providing coil and distributor elements together, including a support having a plurality of contacts, lead connections from said contacts extending ilaterally and downwardly for the spark plug connections, a center contact in said plate for alignment with a distributor shafts rotor contactor, an ignition coil having a core and windings and a connection to said center contact, and molded-on insulation covering said coil and insulation plate and connections in a compact unit.

3. As an article of manufacture, a hermetically sealed ignition device providing coil and distributor elements together, including an insulated support having a plurality of contacts for respective spark plugs, leads con necting from said contacts, a center contact in said plate for alignment with a distributor shafts rotor contactor, an ignition coil having a core and windings and a connection to said center contact, and molded-on insulation covering said coil and insulation plate and connections in a compact unit.

4. As an article of manufacture, a hermetically sealed ignition device providing coil and distributor elements together, including an insulated support having a plurality of contacts, lead connections from said contacts for the spark plugs, a center contact, a coil having a core and windings and a connection to said center contact, and molded-on insulation covering said coil and insulation plate and connections in a compact unit.

References Cited in the file of this patent UNITED STATES PATENTS 1,161,194 Cook Nov. 23, 1915 1,333,004 Vaughn Mar. 9, 1920 2,161,043 Heintz June 6, 1939 2,391,038 Rifenbergh Dec. 18, 1945 2,418,531 Tognola Apr. 8, 1947 2,457,916 Newton Jan. 4, 1949 2,683,287 Cochran et a1. July 13, 1954 

